If you want the enemy to just stagger around a bit and then fall over, then you could add some more frames to each model - some of the damage frames might be good to duplicate, and obviously you'll need to do the dead frames too - and move the head vertexes to somewhere they won't be seen, like inside the body. You'll need to do this manually for each and every MDL file as the Quake models don't contain any headless frames.

Then you need to add locational damage to the engine because the Quake engine doesn't have locational damage. This will need per-poly hit detection - another thing that the Quake engine doesn't have. Without this there is no way of detecting whether or not an enemy has been hit in the head.

Then you need to test it, bug fix it, and make sure that it plays nice with other mods and maps.

If this sounds like too much work (and it is) then just download the patch you were given and study how it was done in the patch, which can be a useful way of learning how to do things for yourself.

We had the power, we had the space, we had a sense of time and placeWe knew the words, we knew the score, we knew what we were fighting for

sevenx wrote:2)"then you could add some more frames to each model"And what soft i need download , that create animation or frames for models ?

I use QuArK and QME to make simple (and sometimes not so simple) changes to existing models. More experienced people here may suggest Blender or similar tools, but they'll require a longer learning curve, including conversion of model formats. For just deforming existing models like mh suggested QME and QuArK are enough.

sevenx wrote:3) And where i can learn about animation for quake ?

There are a handful of experienced modders here, try to make the changes for your own and bring your questions and doubts as they come, I'm sure someone will give useful hints.

I know FrikaC made a cgi-bin version of the quakec interpreter once and wrote part of his website in QuakeC (LordHavoc)